Sheet 1
Create a table to store your data
A..............................B.........................C
1 I.D Number................Name...................Age
2 abc123......................Joe Bloggs............18
3 def456......................David Beckham......28
4
5
etc make the table as big as you want. Then highlight all data in column A except the heading and name the area. To do this click in the box left of the Sum box where it displays the Cell number and name the area I.DNumber. Then Highlight the whole area of data except the headings and name this area aswell. e.g data
Once you have done this go to the sheet where you want it all happen.
Click in cell B9 then click data from the top of the page and then validation. From the first box select list from the drop down list. Leave the second box as it is and then in the bottom box type =I.DNumber. Then ok out of all of that.
This will then make cell B9 a drop down list.
Then go to cell C46 and enter the following into the sum bar
=VLOOKUP(C9,data,2,FALSE) the C9 part looks for wht is in this cell, the data part finds the data from the selected area, the number 2 counts how many cells across from what is in cell C9 and FALSE means
i don't know
hopefully this is clear enough. It is really difficult to explain things via a message board. It would be easier just to send you a spreadsheet with it all on.